(a) Field of the Invention
The present invention relates to a hydraulic garage jack and more particularly, to a swiveling handle mounting mechanism of a hydraulic garage jack, which has the swiveling handle sleeve and the release valve separately installed.
(b) Description of the Prior Art
A conventional hydraulic garage jack has a fixed handle sleeve to hold an operating handle. When the user pumps the operating handle up and down, the hydraulic fluid is pumped out of the fluid chamber to the working fluid cylinder to lift the lifting arm which fits the load accordingly. Because the handle sleeve is fixedly fastened to the frame structure of the hydraulic garage jack, the operating direction of the operating handle is not adjustable.
U.S. Pat. No. 6,086,047 discloses a hydraulic jack, which has a bearing provided under the hydraulic cylinder, such that the handle may be rotated to any direction as required. According to this design, the hydraulic cylinder and the pump are arranged in the member that supports the handle, therefore the lifting stroke is short. Further, the hydraulic jack may fall sideways to the ground easily due to a short wheel base of the rear wheels.
U.S. Pat. No. 6,505,816, issued to the present inventor, discloses a jack with a swiveling handle sleeve. The handle sleeve is locked to a swiveling supporting seat. The swiveling supporting seat passes through the pump and washers to be locked to the base of the jack. Thereby, the handle sleeve may swivel rightwards and leftwards. The release valve is connected to a flexible shaft for controlling the opening and closing of the release valve. A steel ball bearing or a thrust bearing can be installed between the swiveling supporting seat or the base of the jack so that the handle sleeve may swivel freely. The handle sleeve and the swiveling supporting seat have a design for confining the lower limit. However, this design of jack is still not satisfactory in function because the handle sleeve may interfere with the release valve during swiveling.